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Not sure how trustworthy your reference is. But isn't it simple to just run clinfo on your setup, and check what all extensions are supported ?
IMHO cl_khr_fp64 is a extension that is mostly available for high-end products only. So not very sure, but i doubt if low-end trinity/richland iGPUs will support this extension. Their CPU parts should certainly support this extension though.
I have 8650G in my reach. In case you still have problem, i can check the device and let you know the specifics.
Well the issue is I don't have a Trinity/Richland based product yet. I am trying to determine if it supports DP to decide whether I should buy it or not because I need DP support for my work
Rahulgarg, I am with you on this. I have been looking for a new mobile development system and have been waiting to find out for sure if Richland will support double precision fp before I purchase anything. The OpenCL info you referenced does show cl_amd_fp64 being supported and it makes me wonder if this is indeed a driver issue. My understanding was that all APUs Trinity and later would support fp64 but at a much lower ratio in comparison to single precision (E.g. 1/12 instead of 1/4 of high end GPUs). I guess I would look to someone at AMD to confirm this is the case and that it is just a driver issue not providing the OpenCL device info correctly.
The Link above will help understand difference between cl_amd_fp64 and cl_khr_fp64
A small excerpt:
This extension provides a subset of the functionality of that provided
by the cl_khr_fp64 extension. When enabled, the compiler recognizes
the double scalar and vector types, compiles expressions involving
those types, and accepts calls to all builtin functions enabled by
the cl_khr_fp64 extension. However, this extension does not guarantee
that all cl_khr_fp64 built in functions are implemented and does not
guarantee that the built in functions that have been implemented would
be considered conformant to the cl_khr_fp64 extension.
I finally have a Richland (A10-5750) based system and can clarify a few things for anyone who ends up on this thread looking for this info
I have installed Catalyst 13.4. The GPU supports cl_amd_fp64 but not cl_khr_fp64. The GPU can do fp64 ADDs at 1/8th the fp32 rate whereas fp64 MULs and FMAs are done at 1/16th of fp32 rate.
Thus, for Radeon 8650G (which as 384 cores) for example, the throughput for various fp64 instructions is:
1. ADD: 384/8 = 48 adds/cycle
2. FMA: 384/16 = 24 fma/cycle
3. MUL: 384/16 = 24 mul/cycle
I ran my mobile Richland (A10-5750) through CLBenchmark and it returned the following OpenCL Environment with 13.6 beta drivers. I wonder if the full cl_khr_fp64 will be supported in a later driver revision.
I can't be really sure on this, but DP support is more of a Hardware feature. If the iGPU supports cl_amd_fp64 for richland, i would assume it to only support that with future driver releases.